The construction of reinforced concrete walls using the slurry trench technique is basically disclosed in Veder U.S. Pat. Nos. 2,791,886 and 3,310,952 and is now well known in the art and basically comprises a formation of slots or trench sections in the earth in panel form in the presence of a slurry, typically a bentonite slurry, which slurry is displaced by the concrete to form concrete walls. In the case of steel reinforced walls, a slot is excavated in the earth in the presence of the bentonite slurry and a stop end pipe is inserted in one end of the slot and steel reinforcing cage is then lowered into the slot. Concrete is then inserted into the slot or trench to displace the bentonite slurry, such concreting typically being done by the tremie pipe technique. After the concrete has hardened, or solidified to where it is at least self-sustaining, the stop end pipe is removed to form the beginning space for the next succeeding panel section. There have been many efforts in the past to create a positive seal in the joints of such slurry walls but a simple solution to the problem has eluded the art for many years. For example, in Piccagli U.S. Pat. No. 3,796,054, flexible membranes are carried in the stop end pipes which remain in place when the stop end pipe has been removed so as to provide a barrier to the flow of fluids at the joint. However, when located between the side walls of the excavation, Piccagli's joint seals protrude into the next panel section where they interfer with the excavation after the removal of the end stop pipes carrying such seals. Moreover, the seals were limited in extent, being a compromise between the length desired and the need to avoid their protrusion and interference in the excavation of the adjacent panel section.
The present invention provides a simple solution to a problem that has eluded the art for many years. According to this invention, a joint membrane is stowed in a furled or plicated condition during excavation of the adjacent panel section so as to not impede or interfere with the excavation process and, at the same time, be retained in a protected condition so that the excavating implements do not puncture, tear, wrinkle or otherwise damage the integrity of the seal membrane. After the excavation is completed, the stowed portion of the membrane is unfurled or unfolded into the next excavating section just prior to the introduction of the concrete.
If the wall is to have reinforcing steel or armor therein, the joint may have the reinforcement continuous in the manner disclosed in my application Ser. No. 598,632 filed Apr. 10, 1984.